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Topic: Selecting a magnetic compass (Read 1970 times)

I am looking through my options for a compass. This is for a personal project that does not have any strict parameters, although the robot will be loaded with sensors so the type of interface will make a difference. I am thinking I will probably go with I2C since I will already be using a Wii Motion+ and Nunchuck but am willing to consider other options. I will eventually be adding GPS as well. This will be on a chassis with wheelchair motors, most likely mounted on a plastic mast approx 12" above the metal frame (approx 18" above the motors). In addition it will have 2 forms of wireless comm, one of which will likely be WiFi amplified to about 1w (mentioned in case of known issues with noise).

So far I am looking at this Devantech with tilt compensation:

Any recommendations?

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"Never regret thy fall, O Icarus of the fearless flight For the greatest tragedy of them allIs never to feel the burning light."

I doubt in my application the Devantech would be any different, as it's the application, not the compass that's causing problems. I could mount it up on a mast, but would rather not. Instead, I'm going to add a 3 axis gyro as well and combine that data to filter out the noise.

It's not shown in this video, but is works well when I move SAGAR by hand, and the motors aren't running.

@DUKELancelotI would probably prefer a wifi module as opposed to the router, but haven't found one with an SMA connector that I can attach my amp to. If I don't find something I like, I have considered using one of my routers instead.

@madsci1016I assume you upgraded to the HMC6343 for the added tilt compensation. The one I was looking at has 3-4 degree accuracy instead of 2 degrees like yours. From your experience, do you think the extra accuracy makes a significant enough of a difference?

As for mounting my compass, I was considering the mast method to avoid motor noise, but I hadn't really thought about vibrational noise which the mast may well amplify. Also the mast may prove problematic depending on how I mount my pan assembly on top of the robot.

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"Never regret thy fall, O Icarus of the fearless flight For the greatest tragedy of them allIs never to feel the burning light."

@madsci1016I assume you upgraded to the HMC6343 for the added tilt compensation. The one I was looking at has 3-4 degree accuracy instead of 2 degrees like yours. From your experience, do you think the extra accuracy makes a significant enough of a difference?

Held flat, not really. But when i tilted the cheaper one more then 10 degrees, it's reading would go crazy. Also my application didn't really need an compass that was super accurate.